Fastening device



May 19, 1942.

O. VATET FASTENING DEVICE Filed Nov. 3, 1941 Patented May 19, 1942 UNITED STATES PATENT OFFICE;

FASTENING DEVICE Oscar Vatet, Pleasantville, N. Y. Application November 3, 1941,Serial No. 417,630

(Granted under the act of March 3, 1883, as amended April 30, 1928; 371i :.G. 757) 1 Claim.

The invention desc ibed herein may be manufactured by or for and used by the Government of the United States for governmental purposes without the payment to me of any royalty thereon, in accordance with the provisions of the act of April 30, 1928 (ch. 460, 45 Stat. L. 467).

My invention relates to certain improvements in fastening devices, particularly those of the driven class, of which the following is a specification.

fastening device firmly in place without passing through the inner sheathing.

As illustrated in Figures 1 to 3 one form of my improved fastening device may have a series of holes '5 formed along the inner portion of the shank, i. 12., near the point which is provided with an interior bevel 6, viz tapered downwardly and outwardly, there remaining between the holes 5 small sections of metal I which give In the carrying out of low cost housing proj- This action is illustrated in Figure 2 wherein tening device which is illustrated in the accom-j panying drawing wherein like reference characters indicate like parts and wherein:

Figures 1, 2 and 3 represent'one modification of my improved fastening device, Figure 1 being a perspective view thereof, Figure 2 a side elevation showing the action of the device as it enters the inner sheathing, and Figure 3 a side elevation showing the device when fully driven and its action in holding the outer sheathing to the inner sheathing.

Figures 4, 5, 6, 7 and 8 represent another modification of my improved fastening device, Figures 4 and 5 being side elevations thereof, the

latter being partly in section and the former.

showing its action at the start of the. drivin operation, Figure-6, a side elevation showing the sheathing 3 and the inner portion of which isperforated axially to form a series of weaker portions which successfully break and permit the bevelled points to spread the inner portion of the shank out into the inner sheathing 4 as it is being driven, the metal surrounding the perforations forming barbs which bite into the rigidity to the inner portion of the shank, preventing appreciab e spreading of the shank until after it passes through the outer sheathing 3.

it will be see nthat the wedging action of the bevelled points has broken the first two of the metal sections tying'the halves of theshank together, the remaining unbroken metal sections preventing bulging of that portion of the shank which has not as yet-passed through the outer sheathing 3, a

When my improved fastening device is fully driven as illustrated in. Figure 3 the bevelled points 6 cause the sections of the shank to diverge on arcuate paths, the severed metal sections forming barbs I firmly embedded in the material of the inner sheathing 4 thus obtaining a firm anchange for the head to retain the outer sheathing in intimate contact with the inner sheath- In the modification illustrated in Figs. 4 to 8, I have employed the same principles as. heretofore described in. connection with Figures 1 to 3. In this modification however, I use a tubular shank with the perforations 5 arranged to produce four lines of weakness and insert a wedge 8 clearly seen in Figure 5 between the bevelled edges 6 of the prongs. This wedge has a point which centers the wedge and maintains, in conjunction with the cylindrical portion Ill lying within the tubular shank of the fastening device, a short straight path of penetration of the wedge into the inner sheathing. In this case the sloping surface ll of the wedge starts and insures the equal severance of the thin metallic portions 1' which until they pass through the outer sheathing prevent the buckling of the segments of the shank. a

In' this modification I have also added the barbs l2 which are pressed into the material of the inner sheathing and" together with thebarbs 1' insure that the anchorage is even greater than that due to the additional number of prongs. Likewise in the manufacture a! the type illustrated in Figures 4. .to 8 thinner mastructure of the inner sheathing and hold the terial may be used for the shank with the result that the four prongs with their barbs may penetrate the inner sheathing with less destruction of the fibrous or granular structure, the barbs on the top and each side of each section of the shank insuring a firm anchorage with a holding power equal to the strength of the inner sheathing over the area covered by the locus .of the points of the tips of the shanks.

It is, of course, to be understood that the foregoing are merely illustrative of my invention and that modifications may be made therein without departing from the spirit of the appended claim.

One such obvious modification is that the angles of the ends and of the intermediate planes of the shanks and the comparative thicknesses of the weakened bending points will be proportioned for the various degrees of resistance of materials and of the holding power required.

'Having thus described my invention what I claim is: Y

A fastening device adapted to be driven having a head and shank; the latter having a plurality of points tapered downwardly and outwardly from the axis of the shank and adapted to diverge as the fastening device is driven and a series of perforations through the shank spaced so as to leave'frangible portions of said shank between said perforations, whereby said frangible portions prevent buckling of the unembedded portion of said shank and are broken by tension developed by the tapered points said tapered points bending the several severed sections of said shank outwardly during the driving operation.

OSCAR VA'I'ET. 

